1. Field of the Invention
This invention relates to an apparatus for storing calibration and waste fluids for medical devices. More particularly, the present invention relates to a calibration fluid cartridge, including a calibrant fluid container and a waste fluid container, for use in a blood analyzer and other medical devices for analyzing bodily fluids.
2. Description of Related Art
Blood analysis machines and other medical devices require reference solutions to periodically calibrate the system to optimize analytical performance. (For convenience, the remainder of this description will refer to blood analysis machines. It should be understood, however, that such machines are only exemplary and that the present invention can be applied to any type of medical fluid analysis device, such as for urine, spinal fluid, semen, and other bodily fluids.) In such devices, a method of waste collection is required to safely store the expended calibration fluid and potentially hazardous blood (or other fluid) samples. Thus, such devices include containers to hold the calibration fluids as well as waste containers to hold the expended calibration fluid and blood samples.
Many conventional blood analysis machines package the calibration and waste fluids in rigid containers that are attached to the blood analysis machine. Because these containers are rigid, they occupy a great deal of space on the blood analysis machine. Moreover, the rigid containers are expensive and heavy. Other conventional blood analysis machines package the calibration fluid separately and collect the waste fluids into a disposable container via the force of gravity on the waste fluids. These systems are highly complex for the users, as the components require individual monitoring and disposal.
Still other conventional blood analysis machines package the sensor element, calibrant, and waste fluids in individual test cartridges. While this system is user friendly to a certain extent, it is very cost prohibitive, as individual test cartridges must be purchased for every blood sample.
In addition, some blood analysis machines are only concerned with the analysis of electrolytes, rather than gases and electrolytes, and therefore do not require gas tight sealing between a main device housing and the cartridge holding the calibration and waste fluid containers. An example of such a blood analysis machine is disclosed in U.S. Pat. No. 4,649,028, where the cartridge has calibration and waste fluid containers connected to the main housing by a connector and tubing that are gas permeable. Furthermore, a pump is required to pull the calibration fluid from the calibrant bag, because access to the fluids in the bag is by a port on the top of the bag.
Therefore, a need exists for a calibration and waste fluid collection container for use in a blood analysis machine or other medical fluid analysis device, in which the calibration fluids and waste collection container are packaged into a gas tight, user friendly, cost effective, efficient, accurate package. The present invention provides such a calibration and waste fluid collection container.